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Internal state conversion in ultracold gases

J. N. Fuchs·D. M. Gangardt·F. Laloe
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Abstract

We consider an ultracold gas of (non-condensed) bosons or fermions with two internal states, and study the effect of a gradient of the transition frequency between these states. When a $π/2$ RF pulse is applied to the sample, exchange effects during collisions transfer the atoms into internal states which depend on the direction of their velocity. This results, after a short time, in a spatial separation between the two states. A kinetic equation is solved analytically and numerically; the results agree well with the recent observations of Lewandowski et al.

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J. N. Fuchs, D. M. Gangardt, F. Laloe. 2002-04-26. Internal state conversion in ultracold gases. https://doi.org/10.1103/physrevlett.88.230404

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